Data from: Identifying areas prone to coastal hypoxia – the role of topography

Hypoxia is an increasing problem in marine ecosystems around the world. While major advances have been made in our understanding of the drivers of hypoxia, challenges remain in describing oxygen dynamics in coastal regions. The complexity of many coastal areas and lack of detailed in situ data have hindered the development of models describing oxygen dynamics at a sufficient spatial resolution for efficient management actions to take place. It is well known that the enclosed nature of seafloors and reduced water mixing facilitates hypoxia formation, but the degree to which topography contributes to hypoxia formation and small-scale variability of coastal hypoxia has not been previously quantified. We developed simple proxies of seafloor heterogeneity and modeled oxygen deficiency in complex coastal areas in the northern Baltic Sea. According to our models, topographical parameters alone explained ∼80 % of hypoxia occurrences. The models also revealed that less than 25 % of the studied seascapes were prone to hypoxia during late summer (August–September). However, large variation existed in the spatial and temporal patterns of hypoxia, as certain areas were prone to occasional severe hypoxia (O2 < 2 mg L−1), while others were more susceptible to recurrent moderate hypoxia (O2 < 4.6 mg L−1). Areas identified as problematic in our study were characterized by low exposure to wave forcing, high topographic shelter from surrounding areas and isolation from the open sea, all contributing to longer water residence times in seabed depressions. Deviations from this topographical background are probably caused by strong currents or high nutrient loading, thus improving or worsening oxygen status, respectively. In some areas, connectivity with adjacent deeper basins may also influence coastal oxygen dynamics. Developed models could boost the performance of biogeochemical models, aid developing nutrient abatement measures and pinpoint areas where management actions are most urgently needed

Original hypoxia data

Original data used in: Identifying areas prone to coastal hypoxia - the role of topography, Virtanen, Elina A., Norkko, Alf, Nyström Sandman, Antonia, Viitasalo, Markku. The file contains original hypoxia data, with mean and minimum oxygen concentration, hypoxia frequencies, and binary hypoxia (hypoxia present/absent) observations based on thresholds in the publication. Predictor variables are excluded due to national restrictions

Script for reproducing hypoxia models

Script here is an example script for reproducing the hypoxia models. Parameters listed in the script are for the occasional hypoxia (<4.6 mg L -1) model. Hypoxia data which R script suggests, is a modified version due to national restriction

VALUES – värdering av akvatiskta livsmiljöers ekosystemtjänster

Ekosystemtjänster kan bidra till att synliggöra värden i naturen som människor är beroende av för sin överlevnad och sin välfärd. Värdet av ekosystemtjänster behöver också tydligt och systematiskt integreras i politiska beslut och i förvaltningen av våra gemensamma naturresurser, på alla dess nivåer. Övergödningen av Östersjön är ett fortsatt stort problem. Projektet Values har visat hur kartering, kvantifiering och värdering av ekosystemfunktioner kan användas för att visa på värde och nytta av olika typer av ekosystemtjänster i relation till mänsklig påverkan i form av invasiva arter och övergödning i två studiesystem, djupa sedimentbottnar och grunda kustområden. I rapporten visas att vi för att kunna ta hänsyn till ekosystemtjänster i beslutsfattande och förvaltning, behöver kartlägga dem och övervaka förändringar i deras tillstånd. Studien visar på ett konkret sätt hur begreppet ekosystemtjänster kan komma till praktisk nytta. Den här rapporten är ett resultat från ett av sju projekt inom forskningssatsningen Värdet av ekosystemtjänster och har författats av forskare vid AquaBiota Water Research, SLU och SU Östersjöcentrum. Projektet finansierades av Naturvårdsverkets miljöforskningsanslag

Climate change in the Baltic Sea:2021 fact sheet

Abstract Climate change effects on the Baltic Sea environment are manifold. It is for example expected that water temperature and sea level will rise, and sea ice cover will decrease. This will affect ecosystems and biota; for example, range shifts are expected for a number of marine species, benthic productivity will decrease, and breeding success of ringed seals will be reduced. The impacts will hence affect the overall ecosystem function and also extend to human uses of the sea; trawling will follow the fish towards southern areas, aquaculture will likely face a shift towards species diversification, and the value of most ecosystem services is expected to change — to name a few. This Climate Change Fact Sheet provides the latest scientific knowledge on how climate change is currently affecting the Baltic Sea and how it is expected to develop in the foreseeable future. It is aimed at guiding policy makers to take climate change into account, but also to the general public. Updated Baltic Sea Climate Change Fact Sheets are expected to be published approximately every seven years